Driving mechanism for lehr rolls



June 15, 1937. J. H. REDSHAW 2,084,108

DRIVING MECHANISM FOR LEI-IR ROLLS Filed April 16, 1956 3 Sheets-Sheet l 21 I INVENTOR.

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June 15, 1937. J. H. REDSHAWY 2,034,108

DRIVING MECHANISM FOR LEHR ROLLS Filed April 16, 1956 3 SheetsSheet 5 INVENTOR.

do m /v l-z Qzosflfiw Patented June 15, 1937 DRIVING MECHANISM FOR LEHR ROLLS Joseph H. Redshaw, Homestead Park, Pa., as-

signor to Pittsburgh Plate Glass Company, a corporation of Pennsylvania Application April 16, 1936, Serial No. 74,691

Claims.

The invention relates to driving mechanism for the rolls of vertical lehrs, such as those em-- ployed in the Fourcault and Slinglufi processes in drawing glass sheets continuously from a body of molten glass. The rolls employed in these lehrs which are approximately feet in length are arranged in pairs between whichthe glass lheet is gripped and pulled upward, the glass being cut into sections as it emerges from the top of the lehr. The rolls ordinarily comprise tubular shafts covered with relatively hard asbestos composition, with one roll of each pair fixed and the other movable, counterweights being employed to force the movable roll of each pair u toward its fixed roll to give the necessary traction on the glass sheet. The present invention has for its objects the provision of an improved mounting and drive for the rolls, which will permit of the ready removal and replacement of the individual rolls, which permits the rolls to tilt slightly to adjust themselves to the glass without binding in the bearings and consequent interfering with the smoothness of the drive, and which insures an even, uniform drive of the rolls. One embodiment of the invention is shown in the accompanying drawings, wherein:

Figure 1 is a partial side elevation and partial section on the line II of Fig. 2. Fig. 2 is a vertical section on the line IIII of Fig. 1. And N Fig. 3 is a section on the line IIIIII of Fig. 2,

such section being on a larger scale than those of Figs. 1 and 2. g The drawings show only the upper portion of the lehr construction, but it will be understood that the drive for the lehr rolls in the lehr below the construction illustrated is a duplicate of that illustrated. The lehr frame comprises the end plates l and 2 which extend the length of the lehr and, the side plates 3, 3, shown in Fig. 3. The side plates 3, 3 may or may not be used in the upper portion of the lehr depending upon the degree of cooling desired. A bracket 4 is carried at the upper end of the lehr frame and on this is mounted the electric motor 5, which con- 45 stitutes the power means for driving the vertical shaft 6, which extends downwardly throughout the lengthof the lehr casing and constitutes the means for driving the pairs of lehr rolls. Mounted in the extreme upper portion of the lehr frame .0 are the pairs of buffer rolls 1, l and 8, 8, such rolls being driven from the electric motor '9 and the gear mechanism shown at the right hand side of Fig. 2. These buffer rolls with their driving mechanism constitute no part of the present [5 invention and are merely illustrated to, make the showing of the upper portion of the lehr complete.

Mounted at intervals throughout the length of the lehr are the pairs of traction rolls Ill, l0, I0, etc., and ll, II, II, etc., the rolls ll being mounted in each case in fixed bearings carried by the lehr frame, while the rolls I 0 are mounted in bearings carried by hangers so that they may swing toward and from the fixed rolls, such swinging movement being necessary in order to take care of different thicknesses of glass and inequalities in thickness of the glass sheet which may occur from time to time. The rolls in each case consist of shafts I2, l3, I4, etc., provided with an asbestos covering for engaging the glass sheet l5, this'type of roll being well known in the art.

Mounted in series along the frame plate I of the lehr are the rectangular brackets l6, l1, etc. removably secured by means of bolts (not shown) extending through the openings [8. These brackets are in the form of castings and have shelves Ila (Fig. 2) extending laterally from the bodies of the brackets and provided with bearings 18a for the vertical drive shaft 6. The drive shaft 6 is preferably made up of a plurality of sections is secured together by the couplings 20, 2|, etc., which have key engagement with the shaft sections. When it is desired to remove any one of the brackets, the release of the shaft section i9 is accomplished by sliding the couplings 20 upward so that each coupling is disengaged from the shaft section therebeneath. The brackets are each provided with a pair of depending blocks 22 and in these depending blocks is mounted a countershaft 23 carrying at its end a bevel gear 24 meshing with a bevel gear 25 keyed to the vertical drive shaft.

Mounted on each of the countershafts 23 is a hanger 26 and in this hanger is journalled a short socket shaft 21, which receives the end of the shaft of the movable roll Ill. The socket shaft has keyed to its end a spur gear 28, which meshes with a spur gear 29 keyed to the countershaft. In this manner provision is made for rotating the movable rollers Ill. The other ends of the shafts of the movable rollers ID are supported in bearings carried by the hangers 30, 3|,

, etc., the upper hanger 30 being located inside the able rolls in are caused to move towards the fixed rolls H by the use of counterweights32 carried upon rods 33 and 34 (Figs. 2 and 3), the rods 33 being screwed into the hangers 26, while the rods 34 are screwed into the hangers 30' and 3|.

The shafts of the fixed rolls H are supported at their driven ends insocket shafts 35, as indicated in Fig. 3, such socket shafts being journalled in bearings 36 rigidly secured to the side frame I of the lehr. The socket shaft 35 has keyed to its end a chain pinion 31 (Fig. 1), which chain pinion is in alinement with a chain pinion 38 keyed to the countershaft 23. A sprocket chain 39 passes around the sprocket pinions 31 and 38 so that the roll II is driven from the countershaft. The chain 39 is tightened by a take-up device including an arm 40 carried on the pin 4! and provided with an idler sprocket 42, over which the chain passes. The arm 40 is rotated to tighten the chain by means of the rod 43 carrying the counterweight 44. The other ends of the shafts of the fixed rolls are mounted in fixed bearings carried removably upon the frame plate 2 at the other side of the lehr. The shafts of both the fixed and movable rolls fit into the socket shafts 21 and 35, as illustrated best in Fig. 3, the end of the shaft being slightly rounded and provided with the wedge shaped grooves 45 which are engaged by suitable ribs upon the interior of the socket. This permits the roll shaft to rockslightly with respect to the socket shaft and tends to release any binding effect incident to the roll shaft being slightly out of alinement with the socket shaft. It also permits of the removal of the rolls to the right by a sliding movement without disturbing the driving mechanism. This is accomplished by disconnecting the bearings at the right hand ends of the rolls and pulling them endways across the lehr. It is thus possible to remove the rolls for replacement purposes without interrupting the drawing operation.

The provision for rocking movement has its primary advantage in connection with the rolls III which are mounted for swinging movement. In case the glass sheet becomes of uneven thickness, as often occurs with an unduly thickened. edge or a lump of glass being drawn up in the sheet, the rocking engagement of the shaft of the roll with the socket shaft permits it to tilt without binding at the roll bearings, which binding would tend to cause the roll to stop rotating and produce breakage. This feature is also of substantial utility in connection with the fixed rolls, as it prevents binding at the bearings, due to the sagging of the roll under its own weight when the roll is a long one, and due to bending strain placed on the roll when there is a lump of glass on the side of the glass sheet next to such roll. The rocking, sliding joint between the roll shaft and socket shaft may be formed in various ways, the one shown being preferred. In case it is desired to remove one of the brackets I! with the driving mechanism carried thereby for replacement or repair purposes, this is readily accomplished without interfering with the balance of the driving mechanism. All that is necessary is the release of the shaft section I 9 by the use of the slip couplings 20 and 2| and the removal of the bolts holding the brackets H in place, after which it' may be moved to the left (Fig. 4) away from the lehr casing. This removal is facilitated by first removing the rolls I0 The individual drive mechanisms carried by the various brackets IIhave been found to give a smooth, even drive of the traction rolls without slippage or jumping which would tend to break the glass, and at the same time, permit of the swinging of the movable rolls Ill through a considerable arc to take care of inequalities in the thickness of the glass sheet as heretofore pointed out. Other advantages incident to the simplicity and compactness of the mechanism and the positiveness of the drive of each roll will be readily apparent to those skilled in the art.

What I claim is: I

1. In combination with an upright lehr frame provided along itslength with a series of pairs of rolls with shafts therethrough for drawing a glass sheet upward, one of the .rolls of each pair being fixed and the other movable, a motor at the upper end of the frame, a vertical drive shaft extending downwardly from the motor along one side of the frame and provided with a series of bevel gears, a bracket secured to the frame adjacent the ends of each pair of rolls, a countershaft mounted in each bracket transversely of the drive shaft and provided at its outer end with a bevel gear meshing with one, of the bevel gears on the drive shaft, said countershafts also each having secured thereon a spur gear and a chain pinion,

' a hanger mounted on each of the countershafts in which the end of one of the movable roll shaft ends is journalled, a hanger in which the other end of each of the movable roll shafts is journalled at the other side 'of the frame, a spur gear carried by each of said first hangers concentric with the roll shaft supported by such hanger in driving relatin with the roll shaft and meshing with the spur gear on the countershaft, a chain pinion secured to the shaft of each fixed roll, and a drive chain extending around each of said last pinions and the chain pinion on its associated countershaft.

2. In combination with an upright lehr frame provided along its length with a series of pairs of rolls with shafts therethrough for drawing a glass sheet upward, one of the rolls of each pair being fixed and the other movable, a motor at the upper end of the frame, a vertical drive shaft extending downwardly from the motor along one side of the frame and provided with a series of bevel the ends of each pair of rolls, a countershaft.

mounted in each bracket transversely of the drive shaft and. provided at its outer end with a bevel gear meshing with one of the bevel gears on the drive shaft, said countershafts also each having secured thereon a spur gear and a chain pinion, a hanger mounted on each of the countershafts, a socket shaft jcurnalled in each hanger in parallel with said countershaft into whose socket the end of the shaft of each movable roll fits removably with rocking driving engagement, a hanger in which the other end of each of the movable roll shafts is journalled, a spur gear secured on each socket shaft meshing with the spur gear on the countershaft, a chain pinion secured to the shaft of each fixed roll, and a drive chain extending around each of said last pinions and the chain pinion on its associated countershaft.

3. In combination with an upright lehr frame provided along its length with a series of pairs of rolls with shafts therethrough for drawing a glass sheet upward, one of the rolls of each pair being fixed and the other movable, a motor at the upper end of the frame, a vertical drive shaft extending downwardly from the motor along-one side of the frame and provided with a series of bevel gears, a bracket secured to the frame adjacent the ends of each pair of rolls, a countershaft mounted in each bracket transversely of the drive shaft and provided at its outer end with a bevel gear meshing with one of the bevel gears on the drive shaft, said countershafts also each having secured thereon a spur gear and a chain pinion, a hanger mounted on each of the countershafts, a socket shaft journalled in each hanger in parallel with said countershaft into whose socket the end of the shaft of each movable roll fits removably with rocking driving engagement, a hanger in which the other end of each of the movable roll shafts is journalled, a spur gear secured on each socket shaft meshing with the spur gear on the countershaft, a chain pinion secured to the shaft of each. fixed roll, and a drive chain extending around each of said last pinions and the chain pinion on its associated countershaft, said brackets each being provided with a bearing for the vertical drive shaft, and such shaft consisting of a plurality of sections, one for each bracket releasably coupled together above and below said bearings to permit the shaft section to be uncoupled and removed with the bracket.

4. In combination with an upright lehr frame provided along its length with a series of pairs of rolls with shafts therethrough for drawing a glass sheet upward, a pair of socket shafts at one end of each pair of rolls into which the shafts of the rolls fit slidably with driving engagement, one member of each pair of socket shafts being mounted in fixed bearings carried by the lehr frame, and the other member of each pair being supported for swinging movement, removable bearings for the other ends of the shafts of each pair of rolls, one of such bearings which supports the end of the roll shaft whose other end is mounted for swinging movement. also being mounted for similar swinging movement, and the other bearing of such pair being in fixed position on the lehr frame, a driven vertical shaft extending the length of the lehr frame past the series of socket shafts, and driving connections between said vertical shaft and each of said socket shafts.

5. In combination with an upright lehr frame provided along its length with a series of pairs of rolls with shafts therethrough for drawing a glass sheet upward, a pair of socket shafts at one end of each pair of rolls into which the shafts of the rolls fit slidably with driving engagement, one member of each pair of socket shafts being mounted in fixed bearings carried by the lehr frame, and the other member of each pair being supported for swinging movement, removable bearings for the other ends of the shafts of each pair of rolls, one of such bearings which supports the end of the roll shaft whose other end is mounted for swinging movement also being mounted for similar swinging movement, and the other bearing of such pair being in fixed position on the lehr frame, a driven vertical shaft extending the length of the lehr frame past the series of socket shafts, and driving connections between said vertical shaft and each of said socket shafts, the ends of the roll shafts which fit into the socket shafts being formed to permit a rocking movement in said sockets.

JOSEPH H. REDSHAW. 

